Vray animation prepass mode. Problem loading irradiance map for rendering pass

[Husam]

Hi all,

 

I'm rendering out an animation using the IRmap + LC using the animation prepass mode. After doing some research online, I found that this is the quickest solution for rendering animations with moving objects.

 

Since each frame saves out an IRmap for each frame, I thought it would be best to speed up the irradiance map calculation process by using multiple computers. I loaded the same exact max scene with the same rendering settings on multiple computers. Computer 'A' is saving out the IRmap for frames 151-190, computer 'B' is saving 190-240, and so on.

 

Once frames 151-190 were finished rendering, I loaded IRmap 190 to continue rendering.Is it possible to do this? Because now I'm getting some spotches/artifacts so I don't think vray is reading the new IRmaps. I also tried to load the IRmap 151 and start rendering from frame 190, but that didn't work either. Am I missing something here? Please advise. Thank you!

[stormchaser]

here is how i render the scene using animation prepass/rendering mode.

1- prepare the scene, set the primary solution to irmap and secondary to brute force.

2- select "animation prepass" in irmap mode. and render all frames

2B- it is possible to divide the irmap calculation to various pcs, if you have 500 frames, you can render 100 on each pc.

3- place all the frames on each pc. select "animation render" choose the RIGHT PATH and render.

now you can place the selected frames for the particular segment on the pc, but youll need a few extra frames before and after.. for example you want to render the sequence 100-200 frames on a pc, and if your frame rate is set to 2 in irmap mode setting, youll need from frame no. 100-2=98 to frame no. 202. cause vray need extra frames to interpolate. anyway advisable is to copy all the irmap frames to each pc.

now you dont have to load individual frames for particular segments, vray does it itself, all you need to do is to make sure that the irmap solution is present in the right folder, and just specify the frame segments in main rendering setting and it will work.

[Husam]

Hi Sajid,

 

Thank you for your reply. I'm trying to take all measures to avoid Brute force because it takes ridiculously long to render.

With that said, is it really possible to achieve a completely flicker free animation using the IRmap + LC method or is brute force the only sure way to create a flawless animation?

 

I used an interpolation value of 2 and did factor in the 2 before and 2 after for the blending to reduce/remove the flickering. I saved out the IRmaps for frames 151-190 on one machine, and 190-240 on the other machine. Then I copied them all into one folder on one computer. Now here is the problem. When I use 'animation render' I load frame 190 from the folder that contains frames 151-240, which means vray should start referencing from frames 188. But does it? I don't think it is because splotches start to appear from 190. Now my question is, does vray record some kind of call up script within the first rendered frame, in this case, frame 151, that determines the range of frames to be rendered based on when the pre calculation is started and terminated?

Because I noticed in some times, vray would create an initial file with no frame extension for the IRmap load up file, and sometimes, it would just start from the first frame. Very random..Not sure why it's doing that.

 

Maybe the splotches are a result of the render settings?

For Pre calculation I used IRmap + LC

Adaptive DMC image sampler : min 1, max 12.

 

IRmap settings:

-medium- animation mode

- use camera path

- animation (prepass) mode

 

LC settings:

-subdivs 800

-samplse size 0.02

-scale: screen (I know it should be 'world', but for this specfic part of the animation there are no moving objects.)

-single frame mode

- use camera path

 

Rendered out the IRmaps, then loaded them into primary GI. Secondary, none.

 

DMC sampler

adap, 0.85

noise 0.01

min 8

 

 

Could you please make any suggestions on what would be the main setting to tackle to remedy splotches?

 

If anyone could help it would be most appreciated. Thanks!

[stormchaser]

hi mate, can you post the rendered 190th frame where you have the splotches?

regards

[sanmb]

Hi Husam,

Someties we need to render without IR map to avoid splotches.

[Husam]

Hi guys. Thanks for the replies.

 

Sajid, I'll see if I can upload the splotchy frames. I've tried everything, but it seems like the prepass animation mode was not designed to completely eliminate flickering, but rather to minimize/reduce it. Or am I mistaken? I have been reading on other forums about this issue and it seems like alot of people are experiencing the same problem.

 

Sanjay, what combination of GI do you use for best results and reasonable render times? I know brute force is the sure way to go, but is there a time effective solution that can generate good results without the expensive render times?

[sanmb]

Adaptive Subdivision image sampler : min -1, max 2.

 

IRmap settings:

-low

- multiframe incremental mode

 

LC settings:

-subdivs 1000

-samplse size 0.02

-scale: screen (I know it should be 'world', but for this specfic part of the animation there are no moving objects.)

-flythrough mode

Rendered out the IRmaps, then loaded them into primary GI. Secondary, none.

 

DMC sampler

adap, 0.85

noise 0.01

min 8

[Husam]

Hi Sanjay,

Thank you for your help. I was able to get better results using Single frame for IRmap and light cache. The Animation prepass mode was not helpful in removing the flicker.

[sanmb]

My Pleasure.

[Husam]

Hi Husam

I'm making an animation with some moving objects and I have same problem in your topic: http://forums.cgarchitect.com/67583-...ring-pass.html, I've tryed GI prepass and LC but coulnt get a good result.

Could you share your experience how to fix it, thx.

 

Hoa,

 

I was able to get better results by just rendering out the IRmap + lightcache for each frame. Although this is more time consuming than using the animation prepass mode, it's the only way I was able to reduce the artifacting. Otherwise, if you have a super duper render farm, your best solution would be to use the brute force mode.